no matter how you decide to attach the wood to the walls,you should put a strip of foam,available in 50 foot rolls from the big box stores,behind the studs to make a capillary break,otherwise the moisture from the block will get into the wood,mold will follow.

if room size is that important 2" makes a big difference? you ca use 1 1/2" metal studs and track. screw to track to under joists. shoot bottom track to floor using 3/4" nails and powder gun, #2 brown shots should be good, if you find them too powerful? just tap barrel of gun on floor a couple times will lower the power of shot. don't forget wood blocking where'er you'll be nailing? baseboard, door jambs, etc. use a good heavy bead of glue on each stud when hanging drywall and screw securely... studs might rattle closing doors. don't forget vapor barrier between basement walls and new walls. it wouldn't hut to cut some pieces of stud for fastening to plaster and stud for stiffening studs.

simple 25 gauge studs should do what you want, but be very careful as they can and will cut you deep and fast when cutting edges are very sharp! simple tin snips and screw gun is all you need and band aids.